Range
Background
This puzzle appears to be a Nikoli original appearing in 1991.
Puzzle and Goal
An unsolved puzzle consists of a rectangular grid with numbers in some of the cells.
The goal is to color in some of the cells to satisfy the clues.
Rules
The solved grid must satisfy the following conditions:
Numbered clues represent the number of orthogonal neighbors (including itself) that the number can see; colored cells block sight lines.
No two orthogonal neighbors are colored; no numbered cell is colored.
All uncolored cells are orthogonally contiguous.
Other Names
Blackberrier Jam; Kurodoko; Kuromasu
Playable Online